1648: Civil war is devastating England. The privileged world Katherine Ferrars knows is crumbling under Cromwell's army, and as an orphaned heiress, she has no choice but to do her duty and marry for the sake of family.

But as her marriage turns into a prison, and her fortune is decimated by the war, Kate becomes increasingly desperate. So when she meets the enigmatic Ralph Chaplin, she seizes the chance he offers. Their plan is daring and brutal, but it's an escape from poverty and the shackles of convention. They both know if they're caught, there's only one way it can end...